相关疑难解决方法(0)

import java.util.ArrayList;
import java.util.List;

public class IterationBenchmark {

    public static void main(String args[]){
        List<String> persons = new ArrayList<String>();
        persons.add("AAA");
        persons.add("BBB");
        persons.add("CCC");
        persons.add("DDD");
        long timeMillis = System.currentTimeMillis();
        for(String person : persons)
            System.out.println(person);
        System.out.println("Time taken for legacy for loop : "+
                  (System.currentTimeMillis() - timeMillis));
        timeMillis = System.currentTimeMillis();
        persons.stream().forEach(System.out::println);
        System.out.println("Time taken for sequence stream : "+
                  (System.currentTimeMillis() - timeMillis));
        timeMillis = System.currentTimeMillis();
        persons.parallelStream().forEach(System.out::println);
        System.out.println("Time taken for parallel stream : "+
                  (System.currentTimeMillis() - timeMillis));

    }
}

输出:

AAA
BBB
CCC
DDD
Time taken for …